Stars have signed t-shirts for a Twitter Hunt raising funds and awareness for SU2C (Stand Up To Cancer).

Jennifer Aniston (pictured left), Jack Black, Kirsten Dunst (pictured right), Scarlett Johansson, Melissa Etheridge, Charles Barkley and Josh Groban are among a host of stars that have signed t-shirts for the charity hunt going on right now in twenty US cities.

SU2C will twitter clues to help fans find the t-shirts and some of the celebs will also twitter hints themselves.